The custom number transform function is used to map a given number to a target field.
If you've added/updated a map shape before, you'll be used to selecting a source field and a target field. However, when a custom number transformation is used we don't select a source field - the custom number transformation is our data source.
Step 1 In your process flow, access settings for your map shape:
Step 2 Select the add transform button for the required mapping rule - for example:
Step 3 Click the add transform button:
Step 4 Click in the name field to access a list of all available transform functions, then select custom number:
Step 5 Move down to the custom number field and enter your required number - for example:
Step 6 Accept your changes:
...then save the transformation:
Step 7 Now you can select a target field in the usual way - for example:
...then:
...then:
Step 8 Once your mapping is complete, the row should be displayed without a source field - for example:
From here you can save changes or add more mapping rules as needed. Next time the process flow runs, the custom number will be mapped to the given target field.